Light travels as transverse waves and can go through the vacuum of space, while sound has longitude waves and needs to travel through something solid. It can’t travel through a vacuum of space like light.
In theory, yes. The 2 problems are the materials used for clinical thermometers, & the temperature capacity of the clinical thermometer. If anything, change the material & extend the measurement threshold. At that point, it wouldn´t be used for clinical garbage anymore.
